Nedum Onuoha slid in a second and Sylvinho hammered a third as City regained control, but Dedryck Boyata's own goal set up a frantic finale.
Robinho had the final word, though, lashing in to settle a topsy-turvy tie.
It was a terrific strike to cap a typically pulsating encounter, as City boss Roberto Mancini was given a crash course in the ways of the FA Cup.
Robinho's strike also provided an interesting subtext to the game amid speculation the 25-year-old has played his last game for the club.
The playmaker was reported to have told Brazilian radio on Sunday that he has been given permission to return to his homeland on loan for the rest of the season, though when asked after the game whether Robinho would be staying, Mancini said: "I think so."
But if this was his last appearance in a City shirt, the Brazilian will be grateful to have rounded off an otherwise muted display with an emphatic finish at the back end of a compelling match in which Scunthorpe played a full part.
This season, Robinho hasn't fully recovered from injury and hasn't played much football, but people still expect him to be brilliant every time he plays united09/10champions This year's competition has already seen the likes of Manchester United, Liverpool and Arsenal crash out, but City - without a trophy since their League Cup triumph in 1976 - had been warned against taking United lightly before the match by Mancini.
And the visitors got off to the perfect start when Petrov collected Robinho's pass, stepped around the full-back and lashed a fire-cracker into the top corner from 16 yards with three minutes gone.
If the Premier League side thought Scunthorpe would fall away, though, they were to be surprised as the hosts pushed forward, combining no little ambition with their endeavour and work-rate.
The Championship outfit should have been level on 16 minutes when first Cliff Byrne headed against the bar from six yards out, and then Hayes scuffed a Rob Jones knockdown wide from close in.
But it was not long before the breakthrough came - though City were rightly unhappy the goal was allowed to stand.
Hayes was clearly offside as Gary Hooper hooked the ball back into the box, but that should not take away from a fantastic finish, the striker allowing the ball to drop over his shoulder before volleying crisply past keeper Stuart Taylor.
In five previous meetings, Scunthorpe had lost all five and conceded 24 goals in the process - but they were certainly holding their own in a pulsating Cup tie.
Still, for all their bluster, the moments of true incision were coming from City, and particularly Petrov, who brought a flying save from Joe Murphy in the home goal with a curler on the half-hour mark.
And one such clinical move restored the visitors' lead before the break, Stephen Ireland clipping into the box for the onrushing Onuoha to slide home at the near post.
Undeterred, Scunthorpe, 35 places behind their opponents in the league rankings, emerged from the break with renewed vigour, and it took a flying save from Taylor to tip Sam Togwell's drive over the bar and keep the visitors ahead.
However, when Sylvinho lined up a shot from all of 30 yards and drilled a cracker into the roof of the net with Murphy helpless, Iron's resistance looked - finally - to have been broken.
It could have been four minutes later, and it took a triple save from Murphy - from Abdisalam Ibrahim (twice) and Robinho in a goalmouth scramble - to keep Scunthorpe within a sniff.
A truly topsy-turvy match had another turn in store, though, and when Boyata inadvertently deflected Byrne's shot into his own net from a long throw, it set up a frantic finale.
However, it failed to inspire another Scunthorpe goal and Robinho's class finish at the end put paid to any hopes of an equaliser and a money-spinning replay.
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Sunday, 24 January 2010
The FA Cup
Home Team Score Away Team Time Scunthorpe 2-4 Man City R (HT 1-2) Hayes 29 Boyata (og) 69 Petrov 3 Onuoha 45 Sylvinho 57 Robinho 84 Scunthorpe 01 Murphy 03 Williams 06 Byrne 12 Jones (Milne 82) 15 Mirfin 04 Togwell 08 McCann (Wright 88) 11 Thompson 16 Woolford 09 Hayes (Forte 88) 10 Hooper Substitutes 22 Lillis, 05 Milne, 30 Crosby, 07 Sparrow, 19 Wright, 14 Forte, 17 May Man City 12 Taylor 04 Onuoha 16 Sylvinho 33 Kompany 44 Boyata 07 Ireland (Zabaleta 66) 17 Petrov 34 De Jong (Cunningham 46 yellow card) 10 Robinho (Bellamy 85) 27 Mwaruwari 48 Ibrahim Substitutes 37 Nielsen, 02 Richards, 05 Zabaleta, 08 Wright-Phillips, 18 Barry, 45 Cunningham, 39 Bellamy Ref: FriendAtt: 8,861 SCUNTHORPE MAN CITY Possession Scunthorpe 50% Man City 50% Attempts on target Scunthorpe 4 Man City 12 Attempts off target Scunthorpe 9 Man City 8 Corners Scunthorpe 7 Man City 2 Fouls Scunthorpe 9 Man City 6 Final Result Full Time 90:00+5:06 The referee ends the match. 90:00+3:15 A cross is delivered by Jonathan Forte, Abdisalam Ibrahim makes a clearance. 90:00+0:22 The ball is delivered by Craig Bellamy. 88:27 Centre by Garry Thompson, clearance by Greg Cunningham. 87:13 Substitution Paul Hayes goes off and Jonathan Forte comes on. 87:13 Substitution Josh Wright joins the action as a substitute, replacing Grant McCann. 87:13 Nedum Onuoha concedes a free kick for a foul on Sam Togwell. Kenny Milne restarts play with the free kick. 84:37 Substitution (Man City) makes a substitution, with Craig Bellamy coming on for De Souza Robinho. 83:44 Assist on the goal came from Martin Petrov. 83:44 GOAL - De Souza Robinho:Scunthorpe 2 - 4 Man City De Souza Robinho finds the back of the net with a goal from inside the area to the top left corner of the goal. Scunthorpe 2-4 Man City. 80:49 Substitution Kenny Milne is brought on as a substitute for Rob Jones. 80:49 Effort on goal by Martin Petrov from 20 yards. Save made by Joe Murphy. Outswinging corner taken left-footed by Martin Petrov, Headed effort on goal by Dedryk Boyata from inside the penalty box misses to the right of the target. 80:14 Cliff Byrne concedes a free kick for a foul on Martin Petrov. Martin Petrov takes the direct free kick. 78:40 Rob Jones sends in a cross, Pablo Zabaleta makes a clearance. Outswinging corner taken left-footed by Grant McCann, De Souza Robinho manages to make a clearance. Centre by Grant McCann, Martyn Woolford produces a right-footed shot from deep inside the penalty box which goes wide of the left-hand post. 78:30 Garry Thompson delivers the ball, clearance made by Dedryk Boyata. 76:39 Foul by Benjani Mwaruwari on Rob Jones, free kick awarded. Joe Murphy takes the direct free kick. 76:17 The ball is sent over by Garry Thompson. 75:16 David Mirfin challenges De Souza Robinho unfairly and gives away a free kick. Silvio Sylvinho restarts play with the free kick. 74:14 Free kick awarded for an unfair challenge on Nedum Onuoha by Grant McCann. Martin Petrov restarts play with the free kick. 73:27 Foul by Paul Hayes on Vincent Kompany, free kick awarded. Stuart Taylor takes the direct free kick. 73:11 The official flags Benjani Mwaruwari offside. Joe Murphy restarts play with the free kick. 69:32 Pablo Zabaleta concedes a free kick for a foul on Grant McCann. Free kick crossed right-footed by Cliff Byrne from right channel, Nedum Onuoha makes a clearance. Correction - 68:24 GOAL - Dedryk Boyata:Scunthorpe 2 - 3 Man City Own goal by Dedryk Boyata. Scunthorpe 2-3 Man City. 68:24 The assist for the goal came from Rob Jones. 68:24 GOAL - Cliff Byrne:Scunthorpe 2 - 3 Man City Cliff Byrne gets on the score sheet with a goal from inside the area to the bottom left corner of the goal. Scunthorpe 2-3 Man City. 67:02 Shot from 18 yards by Grant McCann. Vincent Kompany gets a block in. Cliff Byrne takes a shot from just outside the penalty area which clears the crossbar. 66:23 The ball is sent over by Sam Togwell, clearance by Nedum Onuoha. Pass corner from left by-line crossed in by Gary Hooper, Abdisalam Ibrahim manages to make a clearance. 65:17 Substitution Stephen Ireland goes off and Pablo Zabaleta comes on. Correction - 62:37 Martin Petrov takes a shot. David Mirfin gets a block in. Inswinging corner taken left-footed by Martin Petrov from the right by-line to the near post, Nedum Onuoha takes a shot. Joe Murphy makes a save. De Souza Robinho takes a shot. Save made by Joe Murphy. 62:37 Martin Petrov takes a shot. David Mirfin gets a block in. Inswinging corner taken by Martin Petrov from the right by-line played to the near post, Nedum Onuoha takes a shot. Joe Murphy makes a save. Nedum Onuoha takes a shot. Save by Joe Murphy. 62:03 Garry Thompson produces a drilled right-footed shot from deep inside the penalty box which goes wide of the right-hand upright. 59:45 Cliff Byrne fouled by Abdisalam Ibrahim, the ref awards a free kick. The free kick is swung in left-footed by Grant McCann, save made by Stuart Taylor. 58:22 Shot by De Souza Robinho. Comfortable save by Joe Murphy. 58:03 Centre by Martyn Woolford, Stuart Taylor makes a save. 56:31 GOAL - Silvio Sylvinho:Scunthorpe 1 - 3 Man City Silvio Sylvinho scores a goal. Scunthorpe 1-3 Man City. 55:37 A cross is delivered by Paul Hayes, clearance by Silvio Sylvinho. 54:44 Foul by Cliff Byrne on De Souza Robinho, free kick awarded. Silvio Sylvinho takes the direct free kick. 54:03 Martin Petrov produces a left-footed shot from just outside the box that goes wide left of the target. 53:01 De Souza Robinho is ruled offside. Joe Murphy takes the free kick. 52:12 Shot by Sam Togwell. Save made by Stuart Taylor. Outswinging corner taken by Paul Hayes, Rob Jones takes a shot. Save by Stuart Taylor. 50:29 Garry Thompson produces a right-footed shot from outside the penalty area and misses left. 49:57 Short corner taken by Grant McCann from the left by-line, Centre by Gary Hooper, Vincent Kompany makes a clearance. 49:10 The ball is sent over by Martyn Woolford, blocked by Nedum Onuoha. 47:02 Cliff Byrne takes the free kick. 47:02 Booking Greg Cunningham goes into the book for unsporting behaviour. 46:57 Greg Cunningham concedes a free kick for a foul on Sam Togwell. 46:08 Paul Hayes concedes a free kick for a foul on Dedryk Boyata. Vincent Kompany restarts play with the free kick. 45:01 The second half begins. 45:01 Substitution Nigel De Jong goes off and Greg Cunningham comes on. Half Time 45:00+1:08 The referee calls an end to the first half. 45:00+0:47 Stephen Ireland produces a right-footed shot from the edge of the box and misses to the right of the target. 44:39 Assist by Stephen Ireland. 44:39 GOAL - Nedum Onuoha:Scunthorpe 1 - 2 Man City Nedum Onuoha gets on the score sheet with a goal from just inside the penalty area to the bottom right corner of the goal. Scunthorpe 1-2 Man City. 44:23 The ball is crossed by Abdisalam Ibrahim, Marcus Williams makes a clearance. 43:21 A cross is delivered by Stephen Ireland, clearance by David Mirfin. De Souza Robinho takes a shot from 18 yards. Joe Murphy makes a comfortable save. 41:04 Nedum Onuoha produces a cross, save by Joe Murphy. 40:13 Nedum Onuoha fouled by Marcus Williams, the ref awards a free kick. Stuart Taylor restarts play with the free kick. 39:57 Silvio Sylvinho sends in a cross, save made by Joe Murphy. 39:03 The offside flag is raised against Benjani Mwaruwari. Indirect free kick taken by Joe Murphy. 38:07 Shot from outside the penalty box by De Souza Robinho goes wide right of the goal. 36:55 Sam Togwell fouled by Nigel De Jong, the ref awards a free kick. Free kick crossed left-footed by Grant McCann, save made by Stuart Taylor. 36:08 Nedum Onuoha crosses the ball, clearance by Cliff Byrne. 35:09 Garry Thompson challenges Abdisalam Ibrahim unfairly and gives away a free kick. Free kick crossed by Martin Petrov, clearance made by Paul Hayes. 34:07 Abdisalam Ibrahim delivers the ball, Rob Jones makes a clearance. 32:41 Shot from just outside the box by Gary Hooper misses to the right of the goal. 32:12 The assistant referee flags for offside against Benjani Mwaruwari. Free kick taken by Rob Jones. 31:40 De Souza Robinho takes a shot. Joe Murphy makes a comfortable save. 31:17 Silvio Sylvinho takes a shot. Blocked by David Mirfin. 28:56 GOAL - Paul Hayes:Scunthorpe 1 - 1 Man City Paul Hayes finds the net with a goal from inside the penalty box to the top left corner of the goal. Scunthorpe 1-1 Man City. 28:32 The ball is crossed by Garry Thompson, clearance made by Dedryk Boyata. 27:55 Cliff Byrne crosses the ball, clearance made by Vincent Kompany. Corner crossed in by Grant McCann. 27:08 Shot by Martin Petrov. Joe Murphy makes a save. 24:20 Effort on goal by De Souza Robinho from 18 yards. Joe Murphy makes a save. 23:40 Grant McCann takes the inswinging corner, clearance made by De Souza Robinho. 21:27 Effort on goal by Nedum Onuoha from just inside the box goes harmlessly over the target. 19:27 The assistant referee flags for offside against Benjani Mwaruwari. David Mirfin takes the indirect free kick. 16:36 The ball is delivered by Garry Thompson. Correction - 15:14 The ball is swung over by Grant McCann, Cliff Byrne takes a shot. The ball is crossed by Martyn Woolford, Effort from deep inside the area by Gary Hooper misses to the left of the goal. 15:14 Grant McCann produces a cross, Cliff Byrne takes a shot. Martyn Woolford crosses the ball, Effort from deep inside the area by Paul Hayes misses to the left of the target. 14:47 Corner taken short by Grant McCann. 13:32 The ball is sent over by Paul Hayes, clearance made by Dedryk Boyata. 11:48 The official flags Paul Hayes offside. Indirect free kick taken by Nedum Onuoha. 10:09 Martyn Woolford has an effort at goal from outside the penalty box missing to the wide right of the goal. 7:10 The ball is crossed by Paul Hayes, clearance by Vincent Kompany. 3:52 Free kick awarded for a foul by Cliff Byrne on Nigel De Jong. Silvio Sylvinho takes the direct free kick. 2:41 GOAL - Martin Petrov:Scunthorpe 0 - 1 Man City Martin Petrov finds the back of the net with a goal from just outside the box to the top left corner of the goal. Scunthorpe 0-1 Man City. 0:44 De Souza Robinho has an effort at goal from 20 yards. Blocked by Marcus Williams. 0:00 The referee gets the match started. Live text and data provided by The Press Association.